title: Electroacupuncture improves glucose tolerance through cholinergic nerve and nitric oxide synthase effects in rats.
abstract: The purpose of this investigation was to evaluate the effect and mechanisms of electroacupuncture (EA) at the bilateral Zusanli acupoints (ST-36) on glucose tolerance in normal rats. Intravenous glucose tolerance test (IVGTT) was performed to examine the effects of electroacupuncture (EA) on glucose tolerance in rats. The EA group underwent EA at the ST-36, with settings of 15 Hz, 10 mA, and 60 min; the control group underwent the same treatments, but without EA. Atropine, hemicholinium-3 (HC-3) or NG-nitro-L-arginine methyl ester (L-NAME) were injected into the rats alone or simultaneously and EA was performed to investigate differences in plasma glucose levels compared to the control group. Plasma samples were obtained for assaying plasma glucose and free fatty acid (FFA) levels. Western blot was done to determine the insulin signal protein and nNOS to exam the correlation between EA and improvement in glucose tolerance. The EA group had significantly lower plasma glucose levels compared to the control group. Plasma glucose levels differed significantly between the EA and control groups after the administration of L-NAME, atropine, or HC-3 treatments alone, but there were no significant differences in plasma glucose with combined treatment of L-NAME and atropine or L-NAME and HC-3. EA decreased FFA levels and enhanced insulin signal protein (IRS1) and nNOS activities in skeletal muscle during IVGTT. In summary, EA stimulated cholinergic nerves and nitric oxide synthase for lowering plasma FFA levels to improve glucose tolerance.
authors.affiliation: Department of Internal Medicine and Emergency Medicine, Division of Endocrinology and Metabolism, Tungs' Taichung Metro Harbor Hospital, Taichung County, Taiwan.
authors.forename: Rong-Tsung
authors.initials: RT
authors.lastname: Lin
authors.forename: Ching-Yuan
authors.initials: CY
authors.lastname: Chen
authors.forename: Chung-Yuh
authors.initials: CY
authors.lastname: Tzeng
authors.forename: Yu-Chen
authors.initials: YC
authors.lastname: Lee
authors.forename: Yu-Wen
authors.initials: YW
authors.lastname: Cheng
authors.forename: Ying-I
authors.initials: YI
authors.lastname: Chen
authors.forename: Wai-Jane
authors.initials: WJ
authors.lastname: Ho
authors.forename: Juei-Tang
authors.initials: JT
authors.lastname: Cheng
authors.forename: Jaung-Geng
authors.initials: JG
authors.lastname: Lin
authors.forename: Shih-Liang
authors.initials: SL
authors.lastname: Chang
mesh_terms: D000109:Acetylcholine / Q000378:metabolism; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism*; D015671:Electroacupuncture; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005951:Glucose Tolerance Test; D055504:Insulin Receptor Substrate Proteins / Q000378:metabolism; D008297:Male; D009474:Neurons / Q000378:metabolism*; D052248:Nitric Oxide Synthase Type I / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D055504:Insulin Receptor Substrate Proteins; C526296:Irs1 protein, rat; D052248:Nitric Oxide Synthase Type I; D000109:Acetylcholine